1. Field of the Invention
This invention relates to wind energy conversion devices and more particularly to a novel such device employing vortex type kinetic energy concentration by controllably coordinating adjacent swirls of counter-rotating vortex regions for driving energy extracting propellors thereby performing useful work.
2. Brief Description of the Prior Art
Man's improved technology has wrought tremendous advances in many fields and, in particular, the science of energy conversion influences almost every field of human activity. The wide and varied uses of wind energy as a renewable source forms an integral, essential component of power sources and instruments and the very heart of most devices such as windmills utilized as a power source or generator.
Although energy conversion of ambient wind is one of the oldest forces known to man, only recently have efforts been made to harness the natural forces of wind energy in the form of a practical and efficient power source. Generally, these sources are being designed and fabricated by conventional methods and to standards which have been in use for many years. These designs and methods usually involve the conversion of wind energy into mechanical work by employing such elements as windmills or the like utilizing impingement of wind against propellors, sails and other mechanical means.
Wind energy has for many years been employed in agricultural devices such as water pumps; however, these wind devices generally are unsuitable for developing sufficient power to operate under conditions requiring a substantial loading of the power source such as may be used for a wide variety of high energy tasks as in hydrodynamic pumping, power generation and other mechanical and hydraulic apparatus when the power source is heavily loaded at all times.
Improvement in primary power sources incorporating natural wind forces which are permitted by modern technological approaches and conceptual improvement can greatly reduce the cost of such primary power sources and make the power source more durable, long lived and more compact by effecting the controlled collection and concentration of the natural wind energy so that a significant change in unsteady forces results whereby major mechanical energy extraction can be effected.
In the past, a number of devices have been made to effect a controlled usage of wind power employing the extraction of energy from a renewable wind source involving the direct impingement of wind against a horizontal or vertical axis windmill. This direct approach in the megawatt power regime requires propellor diameters which are extremely large and, as such, encounter significant oscillating centrifugal and gravity loads when exceptionally large windmills are employed. These loads have a large impact upon the safety, cost, and fatigue life of conventional windmills of large size.
These factors generally limit the top wind speed at which the device can be operated and above which the device must be shut down. Moreover, the huge gyro movement that must be overcome to swing the propellor plane into the wind is a major design factor.
In some recent instances, vortex augmentation has been coupled to turbine generators by employing a variety of diffuser shrouds, divergent ducts and wing configurations for forming twin vortices. Kinetic energy is captured from the vortices for driving the turbines. When conventional "S" ducts are employed (such as in aircraft power-plant air intakes), the airflow does not stay parallel to the duct centerline, but becomes highly angular and creates counter-rotating regions of high angular momentum. Unequal pressure distribution on the engine fan and undesirable and unexpected net lifting forces on the aft end of the engine duct supporting structure occur. In studying this phenomena, however, one begins to realize that in the conversion from linear momentum to angular momentum, energy conversion factors also are involved. In probable recognition of this point, a prior wind converter employing a delta wing configuration for producing a rolled-up vortex region immediately ahead of fan blades or rotors has been described; however, the position of the rotors is too close to benefit sufficiently from vortex roll-up (among other factors (loss of downwash) also tending to diminish effectiveness).
Accordingly, a long standing need has existed to provide a new approach to the utilization of wind energy as a renewable source. Such a new conceptual approach would employ vortex-type kinetic energy concentration so that for the same power applied, propellor diameters would be permitted to be smaller by a factor of at least two with an accompanying savings in cost, complexity, noise, electromagnetic interference, and associated fatigue-life factors.